If within 30 days after the service of any notice as aforesaid the persons giving and receiving the notice do not enter into an agreement for the erection of a fence, and the mode and time of erecting the same and the cost thereof, and if the person receiving the notice shall not serve on the person giving the notice an objection as specified in the manner provided by section 10 , then the person giving the notice may proceed to –

(a) erect a sufficient or rabbit-proof fence, as the case may be; or

(b) convert any existing fence into a rabbit-proof fence –

in accordance with the terms of the notice, and may within two years after the completion of the fence or such conversion recover from the person to whom notice was given in any court of competent jurisdiction one-half of the actual cost of the construction or conversion of the fence, together with interest thereon at the rate of 6 per cent per annum from the date of the completion or conversion.